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Title: About IEEE standards 802.3ab -802.3z Post by: JayOni on May 31, 2011, 06:58:39 PM Ok most of these standards are pretty straight forward and I should have them learned by the end of the day but I do have a few questions which I hope I can get answered before I go to sleep in 4 hours.
1000Base-T (1,000 million bites per sec base twisted pair) falls under both 802.3ab (1Gb Ethernet technology that runs over 4 pairs of cat 5 or better) and 802.3af (specifies PoE, requires cat5 or better) Question 1: Is just that I want to make sure 1000Base-T can fall under more than one standard. I haven't seen much standards except 802.2, 802.3, 802.5, 802.11, 802.16 and the ones im learning now so im not really sure..... if one thing can have multiple standards imposed on it at the same time. 802.3z is defined as 1,000 Base Ethernet technologies. Question 2: The book says that only 1,000base-SX and 1,000base-LX fall under this.... but what about 1,000base-T? Sounds to me that 1,000base-t should fall under 802.3z to but the book doesn't say it does. 802.3ae is defined as 10-Gb Ethernet technologies Question 3: The book lists all the 10-Gb ones (10Gbase-SR, 10Gbase-SW, 10Gbase-LR, 10Gbase-LW, 10Gbase-ER and 10Gbase-EW), except for 10Gbase-T shouldn't 10GBase-T fall under standard 802.3ae? I'm going back to learning the rest of these standards hope to get some help. Title: Re: About IEEE standards 802.3ab -802.3z Post by: tturner on June 01, 2011, 06:04:17 AM Question 1 - 1000BaseT is just Ethernet over copper at Gb speeds. As you've seen there are standards for standard Ethernet and POE enabled Ethernet.
Question 2 - 802.3z is Ethernet over fiber optics. 1000BaseT does not use fiber hence that is why your book does not list it under the 3z entry Question 3 - 802.3ae is 10Gb over fiber. See question 2. Don't get too caught up in the 1000Base(whatever), really the only thing that refers to is the physical medium (and associated characteristics like attenuation) and the speed. Title: Re: About IEEE standards 802.3ab -802.3z Post by: JayOni on June 01, 2011, 05:24:31 PM Ya i found that out later at school while i was researching it. My book left out the fiber part of the standard so I got confused. And its not just the cert I need to pass I need to maintain my 4.0 average so I actually do need to know all that kinda stuff lol. Anyways although I didnt get it the response time i still appreciate it im off to beef up on my network vocab and topologies
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